Summary Among individuals of European Ancestry (EA), genome‐wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) and polygenic risk scores (PRSs) associated with non‐Hodgkin lymphoma (NHL) risk. We evaluated subtype‐specific PRSs, based on established EA‐SNPs, in Israeli Jews (IJ) and Palestinian Arabs (PA) and performed a GWAS in the combined ethnic groups to identify new loci. We included three common pathologically confirmed subtypes: diffuse large B‐cell (DLBCL), follicular (FL) and marginal zone (MZL) lymphomas. Controls were frequency matched to cases by age and sex. Among 752 IJ (201—DLBCL; 130—FL; 54—MZL/367—controls) and 593 PA (203—DLBCL; 41—FL/349‐controls), we computed PRSs weighted by EA‐derived effect estimates and used logistic regression models adjusted for confounders. In the combined ethnic groups of IJ and PA, subtype‐specific PRSs were significantly associated with the corresponding subtype, with a 1.69‐fold, 2.21‐fold and 2.26‐fold risk for DLBCL, FL and MZL, respectively; however, these effect sizes were attenuated compared to those reported in EA and varied by ethnicity. In the GWAS of the combined ethnic groups, two novel SNPs in the 6p21.32 locus were associated with DLBCL risk. Additional GWAS studies are needed among Jewish and Arab populations to improve genetic risk prediction for NHL in these ethnic groups.
Physical activity and the risk of non‐Hodgkin lymphoma subtypes: A pooled analysis
AbstractNon‐Hodgkin lymphoma (NHL) is composed of a heterogeneous collection of subtypes with considerable differences in genetics, biology and aetiology. Studies to date on physical activity and NHL risk have not had sufficient sample size to evaluate whether associations differ by subtype. We pooled data from nine case‐control studies to examine the association between moderate‐to‐vigorous intensity physical activity (MVPA) and risk of NHL overall and by subtype (diffuse large B‐cell lymphoma, follicular lymphoma, chronic lymphocytic leukaemia/small lymphocytic lymphoma, marginal zone lymphoma and mature T‐cell lymphoma). A total of 5653 cases and 9115 controls were included in the pooled analysis. Physical activity was harmonised across nine studies and modelled as study‐specific tertiles. Multinomial logistic regression was used to estimate the association between physical activity and NHL, adjusting for confounders. The overall odds of NHL was 13% lower among participants in the most active tertile of MVPA compared to the least active tertile (adjusted odds ratio = 0.87, 95% CI = 0.80, 0.95). Similar decreases were observed across NHL subtypes. In summary, in this pooled analysis of case‐control studies, physical activity was associated with a modest risk reduction for each NHL subtype examined and with overall NHL.
B-Cell NHL Subtype Risk Associated with Autoimmune Conditions and PRS
Abstract Background: A previous International Lymphoma Epidemiology (InterLymph) Consortium evaluation of joint associations between five immune gene variants and autoimmune conditions reported interactions between B-cell response-mediated autoimmune conditions and the rs1800629 genotype on risk of B-cell non–Hodgkin lymphoma (NHL) subtypes. Here, we extend that evaluation using NHL subtype-specific polygenic risk scores (PRS) constructed from loci identified in genome-wide association studies of three common B-cell NHL subtypes. Methods: In a pooled analysis of NHL cases and controls of Caucasian descent from 14 participating InterLymph studies, we evaluated joint associations between B-cell–mediated autoimmune conditions and tertile (T) of PRS for risk of diffuse large B-cell lymphoma (DLBCL; n = 1,914), follicular lymphoma (n = 1,733), and marginal zone lymphoma (MZL; n = 407), using unconditional logistic regression. Results: We demonstrated a positive association of DLBCL PRS with DLBCL risk [T2 vs. T1: OR = 1.24; 95% confidence interval (CI), 1.08–1.43; T3 vs. T1: OR = 1.81; 95% CI, 1.59–2.07; P-trend (Ptrend) < 0.0001]. DLBCL risk also increased with increasing PRS tertile among those with an autoimmune condition, being highest for those with a B-cell–mediated autoimmune condition and a T3 PRS [OR = 6.46 vs. no autoimmune condition and a T1 PRS, Ptrend < 0.0001, P-interaction (Pinteraction) = 0.49]. Follicular lymphoma and MZL risk demonstrated no evidence of joint associations or significant Pinteraction. Conclusions: Our results suggest that PRS constructed from currently known subtype-specific loci may not necessarily capture biological pathways shared with autoimmune conditions. Impact: Targeted genetic (PRS) screening among population subsets with autoimmune conditions may offer opportunities for identifying those at highest risk for (and early detection from) DLBCL.
Shared Medical and Environmental Risk Factors in Dry Eye Syndrome, Sjogren’s Syndrome, and B-Cell Non-Hodgkin Lymphoma: A Case-Control Study
Objectives. To assess whether there are shared exposures associated with Sjogren’s syndrome (SS), dry eye syndrome (DES), and B-cell non-Hodgkin lymphoma (B-NHL), in order to determine whether they are etiologically related. Methods. In a clinic-based case-control study, 702 participants (91 SS, 120 DES, 211 (age and sex frequency-matched) controls, and 280 B-NHL cases) were recruited and interviewed regarding exposures, medical history, and family history. Results. Female predominance was noted in SS (ratio 9.2 : 1). Eye dryness was severest in SS compared to DES and controls (P<0.001). Compared to controls, alcohol consumption was inversely associated with NHL, DES, and SS (odds ratio OR=0.47, 95% confidence interval (CI): 0.31-0.71; OR=0.54, 95% CI: 0.33-0.88; and OR=0.26, 95% CI: 0.14-0.49, respectively), while a previous history of infection requiring hospitalization was positively associated with all three conditions: NHL (OR=1.92; 95% CI: 1.23-2.99), DES (OR=3.29; 95% CI: 1.97-5.47), and SS (OR=4.74; 95% CI: 2.66-8.44). NHL patients were more likely to report first-degree relatives with hematologic cancer, while having first-degree relatives with an autoimmune disease (AID) was associated with SS (OR=5.25; 95% CI: 2.59-10.63) and DES (OR=3.55; 95% CI: 1.83-6.91) compared to controls. Conclusions. Some exposures are associated with all three conditions (such as an inverse association with alcohol consumption and a positive association with serious past infection), while a family history of AID appears to be shared by DES and SS, but not NHL subjects. Shared risk factors for all three conditions indicate possible mutual etiological pathways.
HLA Class I and II Diversity Contributes to the Etiologic Heterogeneity of Non-Hodgkin Lymphoma Subtypes
AbstractAlthough autoimmune diseases (AIDs) are known to predispose to non‐Hodgkin lymphoma (NHL), their association with NHL prognosis has rarely been investigated. We examined associations between autoimmunity and B‐cell NHL onset by comparing AID history (determined by self‐report and medication review and supplemented by chart review where possible) among 435 adult B‐NHL patients in Hadassah‐Hebrew University Medical Center, diagnosed 2009‐2014, and 414 age‐and‐sex frequency‐matched controls. We examined AIDs as a whole, B‐ and T‐cell–mediated AIDs, and autoimmune thyroid diseases. Among cases, we used Kaplan‐Meier and Cox regression models to assess the association of AID with overall survival and relapse‐free survival, adjusting for prognostically important patient and disease characteristics such as Ki67% staining, International Prognostic Index, rituximab treatment, and histological subgroup.Autoimmune diseases were associated with B‐NHL (odds ratio [OR] = 1.95; 95% confidence interval (CI), 1.31‐2.92), especially AIDs mediated by B‐cell activation (OR = 5.20; CI, 1.90‐14.3), which were particularly associated with marginal zone lymphoma (OR = 19.3; CI, 4.59‐80.9). We found that time to relapse for all B‐NHL patients with AIDs was significantly shorter (mean of 49.21 mo [±3.22]) than among patients without AID (mean of 59.74 mo [±1.62]), adjusted hazard ratio [HRadj] = 1.69 (CI, 1.03‐2.79). Specifically, in patients with diffuse large B‐cell lymphoma, of whom 91.8% had received rituximab, a history of B‐cell–mediated AIDs was associated with shorter relapse‐free survival and overall survival, HRadj = 8.34 (CI, 3.01‐23.1) and HRadj = 3.83 (CI, 1.20‐12.3), respectively.Beyond confirming the well‐known association between AIDs and B‐NHL, we found that AID is an adverse prognostic factor in B‐cell lymphoma, associated with a shortened time to relapse, suggesting that there are specific therapeutic challenges in the subgroup of patients suffering from both these diseases. Further work is required to address mechanisms of resistance to standard treatment in the setting of AID‐associated B‐NHL. In the era of immunotherapy, these findings have particular relevance.